The invention relates to a low tire pressure warning system and more particularly, for a system designed primarily for the purpose of warning the driver of a trailer towing vehicle that one of the tires of the tandem axle trailer is going flat or is insufficiently inflated.
One of the nuances of towing a tandem axle trailer is that it is very difficult to detect the loss of air in one of the trailer tires before the tire has been ruined. In many instances, the driver is not alerted in time to stop the towing vehicle before the tire casing has been chewed up and in some instances, portions of the tire casing are ripped free and may do damage to electrical wiring running beneath the frame of the trailer.
Attempts have been made in the past to design a signaling system to warn the driver of the trailer towing vehicle that there is insufficient air in one of the tires. One such system is described in U.S. Pat. No. 2,957,058. This system requires a special walking beam structure with oscillating shackles to be installed on the trailer and attachment to the leaf spring. The system of this patent has never become popular presumably due to the need for modification of the existing suspension system of the trailer before it can be installed on the trailer.
A latter attempt to devise another type of low tire pressure warning system was disclosed in U.S. Pat. No. 3,614,122. This system also has the same drawback as the previously described system, in that the existing suspension of the trailer must be modified with a specially configured walking beam.
It is an object of the invention to provide a signal to the driver of the towing vehicle when one of the tires starts to become deflated or the air pressure in one of the tires is not sufficient to properly support the load carried.
It is also an object of the invention to provide a low tire pressure warning system constructed in a manner whereby it may be utilized on substantially all tandem axle trailers.
It is a further object of the invention to provide a warning system, including an adjustment feature thereof that will enable the warning system to be adjusted to operate at different predetermined losses of air pressure in any of the tires.
It is an additional object of the invention to provide a low tire pressure warning system that can be installed on substantially all tandem axle trailers without the necessity of modifying or changing any of the suspension structure of the trailer.
It is a final object of the invention to provide a vehicle low tire pressure warning system that is economical to manufacture, install, longlasting and relatively trouble-free.